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Related to pronucleus: Female pronucleus


 (prō-no͞o′klē-əs, -nyo͞o′-)
n. pl. pro·nu·cle·i (-klē-ī′)
The haploid nucleus of a sperm or egg before fusion of the nuclei in fertilization.

pro·nu′cle·ar adj.


n, pl -clei (-klɪˌaɪ)
(Biology) the nucleus of a mature ovum or spermatozoan before fertilization
pronuclear adj


(proʊˈnu kli əs, -ˈnyu-)

n., pl. -cle•i (-kliˌaɪ)
the haploid nucleus of either the sperm or ovum that unites with the opposite-sex nucleus during fertilization.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pronucleus - the nucleus of the ovum or sperm after fertilization but before they fuse to form the nucleus of the zygote
cell nucleus, karyon, nucleus - a part of the cell containing DNA and RNA and responsible for growth and reproduction
References in periodicals archive ?
Without appearance of an additional female pronucleus (PN) caused by non-extrusion of the second polar body (PB), this phenomenon would have escaped detection.
The continuous monitoring of the progress of the embryo development is possible by following the key indicators of this process (both positive and negative) such as formation of the pronucleus, early cleavage, cell cycle intervals, synchronization of cell division and initiation of blastulation, and multinucleation, etc.
When several spermatozoa penetrate the oocyte, the DNA de-condensation is difficult, probably due to intense competition for factors involved in the process of pronucleus formation (COY et al.
We previously reported that ammonia-activated eggs undergo a form of mitosis, in which the female pronucleus chromosomes duplicate and condense, the nuclear envelope breaks down, and the chromosomes align and then segregate via unusual, anastral "mini-spindles" (Henson et al.
Timing of oocyte activation, pronucleus formation and cleavage in humans after intracytoplasmic sperm injection (ICSI) with testicular spermatozoa and after ICSI or in-vitro fertilization on sibling oocytes with ejaculated spermatozoa," Human Reproduction, vol.
1994) The effect of pig follicular fluid fractions on cumulus expansion and male pronucleus formation in porcine oocytes matured and fertilized in vitro.
Without to ocytes activation, male pronucleus and female pronucleus unable to formed together into zygote.
Microinjection is the method of injecting a foreign gene into the pronucleus of a fertilized egg using a micro-manipulator, for the expression of a foreign gene, which is the most widely used method (Gordon and Ruddle, 1981; Palmiter et al.
Male pronucleus formation and early embryonic development after sperm penetration is inhibited if acolytes have no cumulus cells matured.
This study was aimed to evaluate the xenogenic dog sperm in formation of male pronucleus following injection into the sheep oocytes.
There are several methods have been introduced to create transgenic animals, in these the most common method is the microinjection of a transgene into pronucleus of a newly fertilized egg, the introduction of desired gene into embryonic stem cells and the transgenic somatic cell nuclear transfer (TSCNT) which is the variant of SCNT.